Straight Dope

"In the spring of 2012, the aluminum manufacturers signed a memorandum with Canada's Orbite Aluminae, which is currently finalizing the testing of its technology to produce alumina by acid leaching kaolin clay deposits and other low-grade ores. Deripaska decided to purchase that technology and build a plant in Eastern Siberia where there are enough raw materials to produce alumina. Vladislav Solovyov promised that this project would make it possible to avoid the use of imported bauxite.

Paradoxically, however, the Russian National Aluminum-Magnesium Institute (VAMI), which is currently owned by UC RUSAL, was already acid leaching kaolin clay back in the Soviet era and claimed the technique had a bleak outlook. Employees of the institute told this columnist from RusBusinessNews that Orbite hasn't invented a new method at all, but merely reproduced the old Soviet process. The scientists claim that this agenda is being pushed by those with insufficient expertise, because it is not possible to extract millions of tons of metallurgical alumina from kaolin clay - only a small output of high-purity alumina is feasible, which would be suitable for the manufacture of synthetic semiprecious stones. It is no coincidence that the Canadian aluminum company Alcan (purchased by Rio Tinto in 2007) is not interested in the technology." VladimirTerletsky Columnist, RusBusinessNews January 31, 2013